Amy Adams and Isla Fisher have a lot in common. So much so, in fact, that it鈥檚 not uncommon for people to mistake the actresses for one another鈥 including other celebrities. As the Keeping Up With the Joneses star revealed to Jimmy Kimmel, even Lady Gaga can鈥檛 always keep the two straight.

鈥淚 usually correct them. Sometimes I don鈥檛,鈥 she says of people that mix up the two. Upon seeing Gaga at a Vanity Fair Oscars party, for instance, Fisher says chose to stay mum. 鈥淭he crowd鈥檚 part, and there鈥檚 Lady Gaga!鈥 she recals. 鈥淎nd she鈥檚 heading right towards me, And she says, 鈥楾hank you, your performance in American Hustle, Amy鈥︹ and I鈥檓 thinking, 鈥極hmygosh, it鈥檚 Lady Gaga, I love her so much, I don鈥檛 want to tell her the truth, so I just gracefully thanked her, bowed my head.鈥 (We can鈥檛 say we blame her 鈥 we鈥檇 probably have done the same!)

The mother of three says that things got a little sticky, however, when the singer wanted to dissect the performance further, right around the same time that the REAL Amy Adams entered the room. 鈥淪o I said, 鈥楾here鈥檚 Isla Fisher,鈥 she joked. 鈥淪he鈥檚 not even nominated for anything, what鈥檚 she doing here?鈥

After reliving yet another instance in which she was forced to attempt to sing a tune from her Hollywood twin鈥檚 role in Enchanted for adoring fans, she told the talk show host that she鈥檚 finally ready to set the record straight with a helpful (and hilarious!) PSA to the world.

鈥淗ello. I鈥檓 Isla Fisher, and I鈥檇 like to clear something up,鈥 she begins in the skit. 鈥淚 am NOT Amy Adams. Amy Adams, and I, are completely different people.鈥

Walking us all through the subtle differences between the two (鈥淎my Adams鈥 hair is auburn red. Mine is *light* auburn red鈥), Fisher, 41, pleads her case that not all famous redheads (Jessica Chastain and the Wendy鈥檚 mascot included) are interchangeable.

Watch her PSA in all its entirely above, and see you if can tell these two apart!

Are you able to separate the two? Tell us over @BritandCo.

(Photo via Kevin Winter/Getty)